Surefire EP4 Sonic Defenders Plus are high-performance hearing protectors with a triple flange.
EP4 Sonic Defenders Plus effectively protects your hearing, but do not disrupt your ability to hear normal surrounding sounds and conversations. Provide perfect protection from continuous noise (for example, operating noise of machinery and equipment) as well as from impulsive noise (gunshots, explosions).They have a triple-flanged structure that fits perfectly in the ear and provides Noise Reduction (NRR) of 24 dB. Sounds that are at a safe level can pass into the ear canal, while potentially harmful sounds (above 85 dB) are reduced using a special filter. If you don't want to hear low-level noises or conversations while you're resting(for example while traveling) you can simply close the special cap.
Protectors are made from hypoallergenic polymer used in healthcare.They are soft and pliable and provide comfort even when worn all day. They have patented retention rings EarLock, which use seven contact points to secure protectors in place. A soft, adjustable, triple-flanged body will provide safe noise reduction in the ear canals. Low-profile design allows them to be worn under helmet, hat or mask. They can be used when using a phone, headset or additional hearing protectors. The EP4 Sonic Defenders Plus can also serve as headphones for compatible radio communication systems by simply pulling out a noise reduction filter and connect the headphones. In that case, however, they no longer provide hearing protection. A set of protectors is packed in a practical case and also contains a 66 cm cord.
S - for height up to 1"
M - for height 1"
L – for height above 1”
(1" = about 2.54 cm)
Most people fit a size M.
Closed-cap attenuation coefficient
Frequency (Hz) | 125 | 250 | 500 | 1000 | 2000 | 3150 | 4000 | 6300 | 8000 |
Average attenuation (dB) | 31.7 | 29.3 | 32.9 | 30.5 | 35.6 | 37.2 | 35 | 34.4 | 37.7 |
Standard deviation (dB) | 5.4 | 4.6 | 4.3 | 3.2 | 4.1 | 4.2 | 3.6 | 4.1 | 5.5 |
Open cap attenuation coefficient
Frequency (Hz) | 125 | 250 | 500 | 1000 | 2000 | 3150 | 4000 | 6300 | 8000 |
Average attenuation (dB) | 9.7 | 10.5 | 15.6 | 20.4 | 29 | 32 | 28.2 | 30.2 | 36.9 |
Standard deviation (dB) | 3.7 | 3.4 | 2.4 | 3 | 3 | 5.8 | 5.6 | 5.5 | 5.7 |
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Material | Polymer |
Parts of delivery | pads (1 pair) removable cord |